Water retained in the lube oil system of a...

🔍 Key Concepts

• Lube oil system purpose – lubricating and cooling bearings and gears, while preventing metal-to-metal contact • Effects of water contamination in oil – corrosion, rust, pitting, loss of lubricity, possible sludge/emulsion formation • Gears and bearings in turbines – high-speed, high-load contact surfaces that are very sensitive to surface damage

💭 Think About

• Think about what happens when water and steel surfaces stay in contact under pressure inside reduction gears or bearings. Which option best matches that kind of damage? • Consider whether water mixing with oil would realistically make the turbine run faster, or instead damage specific components over time. • Ask yourself: does water in oil increase or decrease oil’s ability to burn (flash point), and does it make the oil better or worse at cooling?

✅ Before You Answer

• Check which choice describes long‑term damage to metal parts instead of an immediate operational change like speed or temperature alone. • Verify which components in a turbine installation are most vulnerable to corrosion and surface fatigue when water is present. • Eliminate any options that don’t make physical sense when oil is diluted or contaminated with water (think about combustion and cooling properties).

Water retained in the lube oil system of a main propulsion turbine installation is undesirable because it __________.

results in excessive cooling of bearing surfaces

causes the turbine to overspeed

causes pitting of the gear teeth

raises the flash point of the oil to a dangerously high level

🔍 Key Concepts

💭 Think About

✅ Before You Answer